Optical recording medium, information processing device using the recording medium, and data recording method

ABSTRACT

The present invention is directed to a data recordable optical disc ( 2 ), wherein buffer areas for random access (Data Run-in DRi, Data Run-out DRo) for random access are respectively disposed before and after respective blocks (BLK, BLK 1 , BLK 2 ), whereby when recording of new block is started, the block is recorded in the state where respective buffer areas overlap with each other with respect to new block and existing block so that no gap takes place. Signal patterns for Phase Locked Loop (PLL) at the time of data reproduction, Auto Gain Control (AGC), and automatic adjustment of light source power, synchronization pattern, and/or signal patterns used for generation of reproduction clock, and detection of block reproduction end, etc. are recorded within the buffer area.

TECHNICAL FIELD

The present invention relates to a recordable optical recording medium,an information processing apparatus adapted for performing write-onceoperation or rewrite operation of data onto such optical recordingmedium, and a method of recording data onto an optical recording medium.

This Application claims priority of Japanese Patent Application No.2002-189347, filed on Jun. 28, 2002, the entirety of which isincorporated herein.

BACKGROUND ART

In recent years, various recording media for digital data such as DVD(Digital Versatile Disc), etc., have been popularized, and optical discrecording/reproducing apparatuses of large capacity adapted forperforming write-once operation or rewrite operation of data to opticaldiscs such as DVD-R (Recordable), or DVD-RW (ReWritable), etc., whichare recordable recording media, have been put into practical use. In theapparatuses of this kind, data write operation is performed with addressinformation of block included at pits, wobbled grooves or lands, etc.,which are formed in advance on the disc essentially on the errorcorrection (ECC) block basis.

In this instance, it is necessary to consider the system of linkingbetween block and block. With respect to the linking, two systems havebeen proposed until now when roughly classified.

One system is a system in which importance to compatibility with readonly optical disc is attached so that blocks are written in such amanner that they are successive without break in the state where thereis no linking portion. As examples employing this system, DVD-R, DVD-RWand/or DVD+RW are mentioned.

The other system is a system in which compatibility with thereproduction only unit of the reproduction only optical disc isdisregarded so that linking portions, pit portions used for addressinformation prepared in advance, etc., and/or gap portions of thoseportions exist between block and block. For example, DVD-RAM employsthis system.

In the conventional system, there are problems as described below, forexample, in regard to compatibility and/or random accessibility.

First, in the system of writing block without break in the state wherethere is no linking portion between blocks, write position accuracy ofhigh accuracy is required as compared to the system where there islinking area in write operation of block by random access. As a result,the circuit therefor becomes more complicated, and this is disadvantagein point of cost. Moreover, in readout operation, there are instanceswhere phases of channel bits of block to be read out and block precedentthereto becomes discontinuous. For this reason, if such a measure forgiving limitation to the phase relationship of channel bits betweenblocks such as a method of continuously writing block to be read out andblock precedent thereto, etc. is not employed, channel bit phasediscontinuous portion between blocks results in disturbance with respectto PLL (Phase Locked Loop) of read-out clock. As a result, there is thepossibility that read-out of data may not be stable for a time perioduntil the time when PLL is placed in steady state so that read-out dataerror takes place. However, when limitation is given to the phaserelationship of channel bits between blocks, random accessibility and/orpreservation efficiency of data onto the disc may be damaged, e.g.,block precedent to write block also must be written as dummy block, etc.

Further, in the system in which gap portion exists between blocks, inthe case where the reproduction only unit of the reproduction onlyoptical disc is used to attempt to reproduce recordable optical disc,difference between physical specifications between the recordableoptical disc and the reproduction only optical disc must be taken intoconsideration. For example, it is necessary to design reproductionsystem circuit such as Auto Gain Control (AGC), etc., in considerationof the fact that the portion where there is no amplitude, i.e., gapexists in reproduction waveform. For this reason, it is required toswitch operation mode of the circuit between reproduction of thereproduction only optical disc and reproduction ofreproducible/recordable optical disc, or to switch the circuit itself,leading to elevation of the apparatus cost.

As stated above, in the conventional linking form, when importance tocost is attached, it is the actual circumstances that there is nothingbut way to select any one of hardware compatibility with thereproduction only optical disc and random accessibility.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a novel opticalrecording medium, an information processing apparatus using such arecording medium, and a recording method for data which can solveproblems that optical recording media where recording of data ispermitted and information processing apparatuses adapted for performingwrite-once or rewrite operation of data with respect to such opticalrecording media have, which have been conventionally proposed asdescribed above.

Another object of the present invention is to provide an opticalrecording medium, an information processing apparatus using such arecording medium, and a recording method for data which can realizelinking system between blocks which is excellent in compatibility withread only optical recording medium and has random accessibility at thetime of recording and at the time of reproduction inrecording/reproducing apparatus adapted for performing write-once orrewrite operation of data onto recordable optical recording medium.

The optical recording medium according to the present invention isdirected to an optical recording medium in which write-once or rewriteoperation of data can be performed with block including a group of databeing as unit, wherein buffer areas for random access are respectivelydisposed before and after respective blocks, whereby when new block isrecorded, the block is recorded in the state where a buffer areaprovided with respect to the block and a buffer area provided withrespect to an existing block adjacent to the block overlap with eachother.

In the optical recording medium according to the present invention, whenrecording of new block is started with respect to a first block and asecond block which have been already recorded, the block is recorded inthe state where a buffer area disposed immediately before the block anda buffer area disposed immediately after the first block adjacent to theblock overlap with each other, and when recording of the block iscompleted, the block is recorded in the state where a buffer areadisposed immediately after the block and a buffer area disposedimmediately before the second block adjacent to the block overlap witheach other.

In accordance with the present invention, buffer areas are providedbefore and after the block, thereby making it possible to easily performrandom access, and also making it possible to form linking area on thebasis of buffer areas overlapping with each other so that any gap doesnot take place between blocks.

Moreover, the present invention is directed to an information processingapparatus adapted for performing recording or reproduction ofinformation to an optical recording medium in which write-once orrewrite operation of data can be performed with block including a groupof data being as unit, the information processing apparatus includingdata recording means for generating recording channel data in whichbuffer areas for random access are added before and after respectiveblocks to record the data onto an recording medium, whereby whenrecording of a new block is started with respect to a first block and asecond block which have already been recorded, the block is recorded inthe state where a buffer area disposed immediately before the block anda buffer area immediately after the first block adjacent to the blockoverlap with each other, and when recording of block is completed, theblock is recorded in the state where the buffer area disposedimmediately after the block and a buffer area disposed immediatelybefore the second block adjacent to the block overlap with each other.

Further, the present invention is directed to a recording method forperforming write-once or rewrite operation of data with block includinga group of data being as unit, wherein buffer areas for random accessare respectively disposed before and after respective blocks, wherebywhen new block is recorded, the block is recorded in the state where abuffer area provided with respect to the block and a buffer areaprovided with respect to an existing block adjacent to the block overlapwith each other.

Still further objects of the present invention and practical meritsobtained by the present invention will become more apparent from thedescription of the embodiments which will be given below with referenceto the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual view for explaining linking system applied tooptical disc according to the present invention.

FIG. 2 is a view showing bit pattern suitable for PLL and/or AGC, etc.

FIG. 3 is a block diagram showing an information processing apparatus towhich the present invention is applied.

FIGS. 4 to 10 are views for explaining channel data at the time ofrecording/reproduction, wherein FIG. 4 is a view showing the state whereRUB corresponding to one block is recorded, FIG. 5 is a view showing thestate where plural successive RUBs are recorded, FIG. 6 is a viewshowing a configuration example of cluster, FIG. 7 is a view showing aconfiguration example of data run-in, FIG. 8 is a view showing aconfiguration example of preamble, FIG. 9 is a view showing aconfiguration example of data run-out, and FIG. 10 is a view showing aconfiguration example of postamble.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention relates to an optical recording medium in whichwrite-once or rewrite operation of data can be performed with blockincluding a group of data being as unit, an information processingapparatus using such optical recording medium, and a recording methodonto optical recording medium. Particularly, in the case where thepresent invention is applied to an optical recording/reproducingapparatus adapted for performing write-once or rewrite operation of dataonto recordable optical disc, there is realized linking system betweenblocks in which compatibility with read only optical disc is maintainedand also having random accessibility at the time ofrecording/reproduction.

In the linking system in the present invention, buffers havingsufficient sizes for the purpose of easily performing perfect randomaccess are provided before and after blocks including a group of data.Namely, buffer areas for random access are respectively disposed beforeand after respective blocks.

In the following explanation, the buffer area positioned before block iscalled “data run-in” and the buffer area positioned after block iscalled “data run-out”. With respect to these buffer areas, as shown inFIG. 1, at the time of start of recording or at the time of end ofrecording, recording is made in the state where the buffer area providedwith respect to corresponding block and the buffer area provided withrespect to existing block adjacent to the corresponding block overlapwith each other.

In the conceptual view shown in FIG. 1, “BLK”, “BLK1”, “BLK2” representblock, and “DRi” and DRo” respectively represent data run-in and datarun-out.

Processing unit according to recording channel data or reproductionchannel data (recording unit block) consists of blocks and buffer areasbefore and after those blocks. For example, BLK consists of data run-inDRi positioned before the BLK and data run-out DRo positioned after theBLK. It is to be noted that indication is made in the state where threerecording unit blocks are positionally shifted in FIG. 1. In “RUB” whichwill be described later, the recording unit block will be furtherexplained.

“Ov” indicates the range overlapping between data run-in and datarun-out. When recording of block BLK is newly started with respect tothe existing block, the block is recorded in the state where data run-indisposed before existing block and data run-out disposed after blockBLK1 adjacent to the existing block (existing preceding block) overlapwith each other. When recording of block BLK is completed, the block isrecorded in the state where data run-out disposed after the existingblock and data run-in disposed before block BLK2 adjacent to theexisting block (existing succeeding block) overlap with each other.

As stated above, at the time of starting of recording of block, bufferareas overlap with each other between corresponding block and blockbefore the recording start block. Moreover, at the time of recordingend, buffer areas overlap with each other between corresponding blockand block subsequent to recording end block. Thus, it is guaranteed thatno gap is formed between blocks.

The linking area is constituted by already recorded buffer area andbuffer area of block to be newly recorded in regard to recording unitblock. For example, the linking area is constituted by data run-out ofprecedent recording unit block and data run-in of new recording unitblock.

Overlap taking place at the time of recording partially takes placewithin buffer area instead of overlap extending over the entire area inregard to buffer area. In this instance, the area which does not overlap(area within data run-in) has sufficient length as buffer area forsignal processing such as pull-in of PLL, etc. For example, in regard todata run-in disposed immediately before block, in the configurationincluding guard area for overlap at the time of recording, and preamblefor signal processing, it is possible to record signal patterns forpull-in of PLL at the time of data reproduction and AGC within the guardarea or the preamble.

As patterns respectively suitable for pull-in of PLL at the time ofreproduction and AGC, it is preferable to use repetitive patterns of3T/3T/2T/2T/5T/5T shown in FIG. 2. Here, “T” indicates data bitinterval. When data is at “1” level, the state is inverted. Namely, forthe purpose of pull-in of PLL, it is better that mark length is shorter.On the contrary, for the purpose of AGC, RF signal having level in whichamplitude is saturated is required. For this reason, in order to satisfyboth requirements, repetitive pattern of 3T/3T/2T/2T/5T/5T is suitable.

In addition, at the time of data recording, data run-in can also be usedfor Auto Power Control (APC) of laser power. For example, in the casewhere data run-in includes guard area for overlap at the time ofrecording, it is sufficient to record, into the guard area, signalpattern for APC according to power of light source.

Multi-purpose utilization can be made with respect to not only datarun-in, but also data run-out.

The data run-out is buffer area for coping with change of recordingposition by SPS or recording start position accuracy similarly to thedata run-in. Here, “SPS” stands for start position shift, which meansposition shift when start positions of respective recording unit blocksare shifted from the prescribed start position by random channel bit inorder to avoid that disc may be damaged by overwrite operation.

The data run-out can also be used as buffer area in point of time forprocessing in which time is required, such as, for example, waveformequalization processing and Viterbi decoding, etc., at the time ofreproduction. In the case where the data run-out includes postamble fortime adjustment of signal processing, it is sufficient to record, intothe postamble, signal pattern for PLL according to reproduction clock.With respect to this signal pattern, it is preferable to use repetitivepattern of 3T/3T/2T/2T/5T/5T which is suitable for PLL of reproductionclock used for processing in which time is required such as waveformequalization processing and Viterbi decoding processing, etc., at thetime of reproduction.

In addition, at the time of recording end of block, the data run-out canalso be used for APC of laser power.

In the linking system used in the present invention, there is providedmeans for enhancing synchronization establishment of data at the time ofreproduction. For example, in the data run-in, plural synchronizationpatterns having distances and ID information (numbers) which aredifferent from each other can be recorded into preamble for signalprocessing. Namely, synchronization establishment means using pluralfeatures such as not only pattern for synchronization establishment(hereinafter called “sync pattern”) but also distance between syncpatterns or ID numbers of sync is freely used to thereby have ability toeffectively establish synchronization of data. The detail thereof willbe described later.

Further, in the data-run out, plural means for detecting that block datareproduction has been completed are provided. Namely, in the datarun-out, sync patterns for detecting reproduction end of the block aredisposed. For example, as described later, in the case where postamblefor time adjustment of signal processing and the guard area provided foradjustment of recording end position are included, it is sufficient torecord, into the postamble, signal pattern for detecting reproductionend of the block. In practical sense, six times of repetitions of 9Twhich are unique pattern at the block are used to have ability toperform end detection of block.

Then, the information processing apparatus according to the presentinvention will be explained with reference to FIG. 3. The informationprocessing apparatus 1 having recording/reproducing function to whichthe present invention has been applied is an opticalrecording/reproducing apparatus in which hardware such as CPU (CentralProcessing Unit), ROM (Read Only Memory), and RAM (Random AccessMemory), etc. are included.

At the information processing apparatus 1 shown in FIG. 3, there isprovided an optical pick-up (or optical head) 3 for performing read orwrite operation of information with respect to an optical disc 2 whichis optical recording medium. The optical pick-up 3 is moved along theradial direction of the optical disc 2 by movement mechanism (not shown)so that visual field position of the object lens with respect to theoptical disc 2 is controlled. The information processing apparatus 1comprises a spindle motor 4 for rotating the optical disc 2. The spindlemotor 4 is controlled by a motor control unit 5.

The optical pick-up 3 includes semiconductor laser serving as lightsource which emits light beams irradiated onto the optical disc 2, andlight receiving element for receiving return light beams reflected bythe optical disc 2, and serves to converge light beams emitted from thesemiconductor laser onto the optical disc 2, and to receive return lightbeams reflected from the optical disc 2 to convert them into detectionsignal thereof to output it therefrom.

At the optical pick-up 3, there is provided a pick-up control unit 6 forperforming control of the mechanism including actuator for object lensdrive, etc. and feed control of the optical pick-up 3, etc. As theresult of the fact that the actuator for object lens drive is controlledby the pick-up control unit 6, light beams which are irradiated onto thesignal recording surface of the optical disc through the object lens andscan recording tracks formed at the optical disc are focused on thesignal recording surface of the optical disc 2 so that the opticalpick-up 3 is controlled in such a manner to follow the recording tracksto scan these recording tracks. In addition, the optical pick-up 3 iscontrolled by the pick-up control unit 6 so that positions with respectto inner circumference and outer circumference of the optical disc 2 arecontrolled.

Information signal recorded on the optical disc 2, which is obtained byreceiving, by light receiving element, return light beams reflected fromthe optical disc 2, is sent to a reproduction signal processing unit 7.

The reproduction signal processing unit 7 is constituted by using readchannel processor, etc., and its output is delivered to a wobble signaldetecting unit 8, a reproduction data processing unit 9 and the pick-upcontrol unit 6.

Wobble signal detected by the wobble signal detecting unit 8 constitutedby wobble processor, etc. is sent to a wobble information extractingunit (address detector) 10, at which information such as address, etc.which specifies position on the optical disc is extracted.

The wobble signal consists of the so-called mono-tone signal portion,and signal portion in which address information indicating recording orreproduction start position has been caused to undergo MSK modulation.The wobble information extracting unit 10 performs detection anddemodulation of address information from wobble signal to generate anaddress synchronizing signal. It is to be noted that while variousvalues are conceivable with respect to period of wobble signal, 1 wobble(wobble period) is assumed to be 69 channel bits as a suitable value inthe case where, e.g., influence given to recording or reproduction ofchannel bit and/or information quantity of address information are takeninto consideration.

The address information detected at the wobble information extractingunit 10 is sent to a timing (signal) generating unit 11. As a result,recording/reproduction timing (read/write timing) signals of data aregenerated on the basis of the address information. This reproductiontiming signal is sent to the reproduction data processing unit 9 and/ora recording data processing unit 12. In this example, the timinggenerating unit 11 generates a recording position control signalsynchronous with address synchronizing signal and recording clock inaccordance with recording/reproduction start address instruction, etc.from a controller 15 which will be described later to output it tomodulation & synchronizing signal generating section within recordingdata processing unit 12 and demodulation & synchronization detectingsection within the reproduction data processing unit 9.

The reproduction data processing unit 9 receives a signal from thereproduction signal processing unit 7 to perform processing such asdemodulation, synchronization detection and ECC (Error Correcting Code)decoding, etc.

The recording data processing unit 12 performs processing such asmodulation of data, synchronizing signal generation and/or ECC encoding,etc. to send out processing result (signal for recording) to laser driveunit 14.

The recording reference clock generating unit 13 serves to generatereference clock for recording from wobble signal from the wobble signaldetecting unit 8. With respect to data recorded onto the optical disc 2,signal processing is performed on the basis of the recording clocksignal. The recording reference clock generating unit 13 is ordinarilyconstituted by PLL circuit, and its output signal is sent to therecording data processing unit 12 or the laser drive unit 14.

The laser drive unit 14 serves to drive laser light source within theoptical pick-up 3, and controls intensity and light quantity of laser sothat they have desired values and modulates laser beams on the basis ofrecording data at the time of recording. At this time, modulation isperformed with the above-described recording clock signal being asreference signal.

As the controller 15, there are provided controller including interfacemeans with external host unit (host computer, etc.) 16, and controllerincluding interface means with microcomputers for focus servo andtracking servo.

The recording processing is performed mainly by the recording dataprocessing unit 12. Here, with recording clock signal from the recordingreference clock generating unit 13 being as reference signal, ECCencoding processing, interleave processing, DC control processing and(1, 7) PP modulation processing are performed with respect to recordinguser data inputted from the controller 15. “PP” stands for “Paritypreserve/Prohibit RMTR”. Further, generation and addition processing ofsynchronization pattern and data run-in or data run-out are performed.Thus, recording channel data is generated. The detail ofrecording/reproduction channel data will be described later.

In other words, the recording data processing unit 12 constitutes thedata recording unit 17 with respect to the optical disc 2 along with therecording reference clock generating unit 13, the laser drive unit 14and the optical pick-up 3, etc. Recording channel data in which bufferareas for random access are added before and after respective blocks(data blocks) are generated. Thus, information including data and syncpattern, etc., are recorded onto the optical disc 2. It is to be notedthat, although described later, guard area or areas is or are providedat the rear portion of one recording unit block, or at the rearmostportion of successive plural recording unit blocks (see FIGS. 4 and 5).

The controller 15 is connected to the host unit 16 such as hostcomputer, etc., through interface, and serves to performtransmission/reception of data to and from the host unit 16 and toperform control of the entirety of the optical discrecording/reproducing apparatus as the information processing apparatus1.

At the time of reproduction, control is made such that light beamsemitted from the optical pick-up 3 are irradiated onto an arbitraryposition of the optical disc 2. In this control, servo signal sent fromthe reproduction signal processing unit 7 to the pick-up control unit 6is used.

At the reproduction signal processing unit 7, light receiving signalfrom the optical pick-up 3 is processed. Thus, reproduction signal,push-pull signal and servo signal are generated. At the reproductionsignal processing unit 7, AGC (Auto Gain Control) processing, AD(Analog-to-Digital) conversion processing, waveform equalizationprocessing and/or Viterbi decoding processing, etc., are performed withrespect to reproduction signal. Thus, reproduction channel data isreproduced.

The reproduction data processing unit 9 of the succeeding stage detectssynchronization pattern from reproduction channel data on the basis ofreproduction timing signal from the timing generating unit 11 to perform(1, 7) PP demodualtion processing to reproduce user data via interleave(deinterleave) processing and ECC decoding processing. Further, userdata is transferred to the host unit 16 through the controller 15.

The reproduction signal processing unit 7 and the reproduction dataprocessing unit 9 constitute data reproduction unit 18 with respect tothe optical disc 2 along with the optical pick-up 3, etc., and serve toperform not only main processing which is reproduction (restoring) ofinformation, but also various signal processing followed thereby. Forexample, there is conducted processing such that signal pattern recordedat the data run-in is reproduced to use such reproduced signal patternas signals for pull-in of PLL and AGC, or signal pattern recorded at thedata run-in or the data run-out is reproduced to use the reproducedsignal pattern as signal for APC of light source power. In addition tothe above, those processing units take charge of processing such that,in the data run-in, plural synchronization patterns recorded at preamblefor signal processing are reproduced to perform processing forestablishment of synchronization, or in the data run-out, signal patternrecorded at the postamble for time adjustment of signal processing isreproduced to perform processing necessary for generation ofreproduction clock, and/or to perform detection of reproduction endaccording to corresponding block, etc.

It is to be noted that, with respect to push-pull signal generated atthe reproduction signal processing unit 7, reflected light from theoptical disc 2 is received by light receiving elements bisected inparallel to the track tangential direction to detect such push-pullsignal as difference signal between outputs by those bisected lightreceiving elements. Wobble signal is extracted from the push-pull signalby BPF (Band Pass Filter), etc.

In addition, the spindle motor 4 and the motor control unit 5 constituterotation control means for optical disc, and serve to control rotationof the optical disc so that the wobble signal has a predeterminedfrequency. The optical disc on the turn table rotated by the spindlemotor 4 is rotationally driven on the basis of control signal from themotor control unit 5.

Next, the detail of recording/reproduction channel data will beexplained by using FIGS. 4 to 10.

It is to be noted that user data, i.e., data caused to undergotransmission/reception to and from application or Host, etc. is causedto undergo format processing at several stages, such as being convertedin succession in order of “data frame or scrambled data frame→datablock→LDC block→LDC cluster”. Here, “LDC” is abbreviation of “LongDistance error correcting code”, and permits removal of both randomerror and burst error.

Moreover, address and control data of DVR (Digital Video Recording) areconverted in succession in order of “address block→BIS block→BIScluster”. Here, “BIS” stands for burst indicator subcode. BIS code wordincludes address and control data along user data, and is used fordetection of long burst error.

LDC cluster and BIS cluster are multiplexed and modulated so that ECCcluster is provided.

At DVR, data are recorded in the state divided into unit (64 k bytes)called “physical cluster”. 32 data frames of user data 2048 bytes areincluded in the physical cluster. By error correction of LDC and BIS,data is protected.

All data are constituted as one array as shown in the following Table 1,and data are read out along lateral direction of the Table. Further,bits for control of DC component (by DSV) are added to data. The datathus obtained are then modulated. After synchronization pattern isinserted, such data are recorded onto the disc.

TABLE 1 sync 38*2LDC 1*8BIS ↓ words ↓ words

↑ D0 . . . D37 B0 D38 . . . D75 B1 D76 . . .D113 B2 D114 . . . D151 ↑D152 . . . D189 B3 D190 . . . Address 31 Unit0 ↓ . 496

. . Address ↑ Unit14 31 ↓ ↓ Address ↑ Unit15 31 ↓

In this case, “sync” in the Table 1 indicates synchronization portion(sync), “DX” (X=0, 1, 2, . . . ) indicates LDC code word, and “BX” (X=0,1, 2, . . . ) indicates BIS code word.

The LDC code word is interleaved in the diagonal direction of theTable 1. Moreover, the entirety of the physical cluster for addressingis partitioned (divided) into 16 address units (or physical sectors)respectively consisting of successive 31 lines.

Units of recording channel data and reproduction channel data areRecording Unit Block (hereinafter abbreviated as “RUB”). This RUB isadapted so that it starts from Data Run-in area of 2760 channel bits,clusters (physical clusters) which are set of modulated user data andthe synchronization pattern thereof are successive, and it ends at DataRun-out area of 1104 channel bits.

In the channel bit example schematically shown in FIGS. 4 and 5, “1”indicates RUB, cluster indicated by “3” is located next to data run-inindicated in the state where “2” is attached, and data run-out indicatedby “4” is positioned thereafter. In this example, these figures arecodes attached to respective portions. It should be noted that figureitself within “ ” has no meaning.

Data run-in “2” and data run-out “4” provide sufficient buffer areas forfacilitating complete random write or overwrite.

RUB “1” are recorded at predetermined positions designated by address onthe disc by one block or as sequence of successive plural blocks.Namely, RUB is recorded singly or as sequence of successive plural RUBs.In other words, even either one RUB or successive plural RUBs may exist.In the case where one RUB exists, guard area (indicated by “5”) ispositioned at the rear portion of the RUB. With respect to successiveplural RUBs, guard area “5” is positioned at the rearmost portion of thelast RUB. In short, guard area will be recorded after the last RUB. Inthis case, guard area “5” is an area for guaranteeing that gap does nottake place between all two RUBs, and its length is 540 channel bits.

FIG. 4 shows the case where RUB corresponding to one block is singlyrecorded from RUB address N (indicating recording start position ofRUB), wherein guard area “5” is positioned immediately after datarun-out of the RUB.

Moreover, FIG. 5 shows the case where RUBs corresponding to M blocks (Mis natural number of 2 or more) are sequentially recorded with RUBaddress N being as starting point, wherein guard area “5” is positionedimmediately after the “N+M”-th RUB. In the case where M successiveblocks are recorded, data run-in and data run-out do not overlap betweenadjacent blocks of the blocks.

FIG. 6 shows the configuration within one cluster, wherein cluster “3”consists of plural frames indicated by “6”, “6”, . . . .

For example, the number of frames “6” which constitute RUB “1” is equalto 496. Frame “6” consists of frame data indicated by “8”, and sync “7”which is the synchronizing signal thereof, wherein this sync is FS(Frame sync).

Modulated recording frame starts from FS consisting of 30 channel bits.As shown in the following Table 2, seven patterns of FS0 to FS6 aredefined. The modulated recording frame includes 24 bit pattern (bodyportion) which is not in conformity with (1, 7) PP modulation rule, and“Signature” of 6 bits indicating ID (Identification information).

TABLE 2 Sync Number 24-bit sync body 6-bit sync ID FS0 #01 010 000 000010 000 000 010 000 001 FS1 #01 010 000 000 010 000 000 010 010 010 FS2#01 010 000 000 010 000 000 010 101 000 FS3 #01 010 000 000 010 000 000010 100 001 FS4 #01 010 000 000 010 000 000 010 000 100 FS5 #01 010 000000 010 000 000 010 001 001 FS6 #01 010 000 000 010 000 000 010 010 000

In this example, pattern of FS (sync pattern) is determined by modulatedbits, and “1” shown in the bit example in the Table 2 indicatesinversion of signal. Before recording onto the disc, frame sync code isconverted into NRZI channel bit stream.

Moreover, since it is insufficient to identify 31 recording frames byseven kinds of FSs, identification is performed by combination of pluralFSs.

The first recording frame of each physical sector is caused to be FS0(unique frame sync), and other frames are indicated as shown in thefollowing Table 3. The Table 3 shows corresponding relationship of FSwith respect to frame number.

TABLE 3 Frame number Frame Sync Frame number Frame Sync 0 FS0 1 FS1 16FS5 2 FS2 17 FS3 3 FS3 18 FS2 4 FS3 19 FS2 5 FS1 20 FS5 6 FS4 21 FS6 7FS1 22 FS5 8 FS5 23 FS1 0 FS5 24 FS1 10 FS4 25 FS6 11 FS3 26 FS2 12 FS427 FS6 13 FS6 28 FS4 14 FS6 29 FS4 15 FS3 30 FS2

When the Table 3 is used, sync of a certain frame sync and sync of frameprecedent thereto are combined so that identification of recording framecan be made. Thus, it is possible to specify FS from combination of syncaccording to frame number n and sync according to either one of n−1,n−2, n−3, n−4. Even in the case where, e.g., current frame No. isassumed to be 5 and sync (FS1, FS2, FS3) are lost with respect to thefirst, second, and third frames precedent thereto, it is possible toidentify frame from sync (FS3) of the fourth frame precedent by oneframe and sync (FS1) of current frame (fifth frame). The case(possibility) where FS1 comes next to FS3 can take place only atspecific portions in the above Table, i.e., frame numbers 4, 5.

The above description relating to RUB is made as the premise of SPS(Start Position Shift) of ±2 wobbles at the maximum and recording andreproduction position accuracy of ±0.5 wobbles. In this case, overlapportion between RUBs by recording in the case of random access fallswithin the range from 3 to 13 wobbles. In addition, the minimum lengthof data run-in area which is not caused to overlap approximately becomesequal to 27 wobbles. This length corresponds to about one recordingframe, and is sufficient length as buffer area for pull-in of PLL and/orsignal processing.

FIG. 7 shows the configuration of data run-in.

Data run-in “2” consists of guard area (1100 channel bits) indicated inthe state where “11” is attached, and preamble (1660 channel bits)indicated in the state where “12” is attached. The guard area “11” isbuffer area for overlap resulting from SPS and/or start positionaccuracy of overlap recording operation. In addition, the preamble “12”is buffer area for signal processing (lock, taking of synchronization).

The guard area “11” has length of 1100 channel bits, and its channel bitpattern is repetition of 55 times of 01[0]²1[0]²10101[0]⁴1[0]³. Here, inthe representation of 01[0]²1[0]²10101[0]⁴1[0]³, 0 and 1 respectivelyindicate non-inversion and inversion of write channel bit train at NRZI(Non Return to Zero Inverted) onto the disc. Moreover, brackets [ ] andfigures with superscript succeeding thereto indicate repetition of thenumber of times of figures with superscript of pattern within brackets.

The repetitive pattern of 01[0]²1[0]²10101[0]⁴1[0]³ results inrepetition of 3T/3T/2T/2T/5T/5T (see FIG. 2). This pattern is patternsuitable for respective processing of pull-in of PLL at the time ofreproduction and AGC. Namely, for the purpose of pull-in of PLL, it isbetter that the mark length is short. However, for the purpose of AGC,RF signal having level in which amplitude is saturated is required. Therepetitive pattern of 3T/3T/2T/2T/5T/5T is suitable pattern for suchdemand, and is pattern respectively suitable in regard to both features,i.e., pull-in of PLL at the time of reproduction and AGC.

Moreover, the first 5 wobbles of the guard area “11” at the start of therecording sequence can be used for automatic adjustment (APC) of laserpower. Namely, as modulation bit pattern used in APC, [0]²1[0]²10101[0]⁴1[0]³ or pattern optimum for APC can be arbitrarilyselected.

FIG. 8 shows the configuration of preamble.

The preamble “12” has length of 1660 channel bits. This preamble isconstituted by repetitive pattern indicated in the state where “21” isattached (repetitions of 77 times of 01[0]²1 [0]²10101[0]⁴1[0]³),synchronization pattern (sync) indicated in the state where “22” isattached, repetitive pattern indicated in the state where “23” isattached (repetitions of two times of 01[0]²1[0]²10101[0]⁴1[0]³),synchronization pattern (sync) indicated in the state where “24” isattached, and repetitive pattern indicated in the state where “25” isattached (one time of 01[0]²1[0]²10101[0]⁴1[0]³). Here, sync “22” andsync “24” are caused to be above-described FS. In the rule of this FS,sync “22” is. FS[mod({N+4, 7})] (where “mod(x, a)” indicates remainderwhen x is divided by a), sync “24” is FS[mod({N+6, 7})] (where X=0 to 6,and FS[X] corresponds to “FSX” in the Tables 2 and 3). It is to be notedthat this is the case where the first frame succeeding to preamble “12”is FS[N]. For example, in the case where the first FS (hereinafterreferred to as “FFSO”) after preamble “12” is FS0, it is implied thatsync “22” is FS4 and sync “24” is FS6.

Since sync “22”, sync “24” and FFSO are in conformity with generationrule of FS, IDs are different from each other. Thus, even in the casewhere two synchronization patterns among three synchronization patternscannot be detected by disturbance, synchronization of cluster can beestablished in the case where the remaining one synchronization patternis detected and ID of synchronization pattern can be normally read out.In addition, sync “22”, sync “24” and FFSO have distances therebetweenwhich are different from each other (intervals of channel bits aredifferent from each other). For this reason, even in the case where onesynchronization pattern cannot be detected by disturbance among threesynchronization patterns and even in the case where the remaining twosynchronization patterns are detected and IDs of the synchronizationpattern which can be detected cannot be normally read out,synchronization of cluster can be established.

FIG. 9 shows the configuration of data run-out.

Data run-out “4” consists of postamble indicated in the state where “15”is attached (564 channel bits), and guard area indicated in the statewhere “16” is attached (540 channel bits). The postamble “15” is bufferarea in point of time for processing in which time is required such aswaveform equalization processing and Viterbi decoding processing, etc.,at the time of reproduction. In addition, the guard area “16” is bufferarea in which change of recording position by SPS or recording startposition accuracy is taken into consideration similarly to the guardarea “11”.

FIG. 10 shows a configuration example of postamble.

Postamble “15” is constituted by sync indicated in the state where “27”is attached, unique pattern indicated in the state where “28” isattached (01[0]⁸1[0]⁸1[0]⁸1[0]⁸1[0]⁸1[0]⁷), and repetitive patternindicated in the state where “29” is attached (repetitions of 24 timesof 01[0]²1[0]²10101[0]⁴1[0]³). Here, sync “27” is FS0. Moreover, uniquepattern “28” (repetitions of six times of 9T) is unique pattern at RUB,i.e., does not appear at other portions of RUB, and can be used fordetecting end of cluster. Further, repetitive pattern “29” is patternsuitable for PLL of reproduction clock used for processing in which timeis required such as waveform equalization processing and/or Viterbidecoding processing, etc., at the time of reproduction.

Guard area “5” (see FIGS. 4 and 5) has length of 540 channel bits, andits bit pattern is repetitions of 27 times of 01[0]²1[0]²10101[0]⁴1[0]³.In addition, at the last portion of the recording sequence, the lastfive wobbles of the guard area “5” can be used for the above-mentionedAPC for laser beams. As modulation bit pattern used in the APC, it ispossible to arbitrarily select 01[0]²1[0]²10101[0]⁴1[0]³ or optimumpattern for APC.

In accordance with the above-described configuration, merits as shownbelow can be obtained.

In the optical disc recording/reproducing apparatus of large capacityadapted for performing write-once or rewrite operation of data onrecordable optical disc according to the present invention,compatibility with hardware which constitutes read only reproductiononly machine is improved. Namely, it is unnecessary to greatly changethe circuit configuration of the reproduction only machine inconsideration of the fact that existence of gap of reproduction waveformbased on gap between blocks is taken into consideration. Thus, it ispossible to reproduce recordable optical disc by less additional costwith respect to the read only reproduction only machine.

Since the optical disc according to the present invention and theinformation processing apparatus using such optical disc as recordingmedium is excellent in the random accessibility, the optical disc andthe information processing apparatus can exhibit excellent performancealso in the case where they are applied to all optical discs for AV(audio, video) or computer storage, and/or optical discrecording/reproducing apparatuses.

Since the optical disc according to the present invention can use thelinking area in multi-purpose manner, area which cannot be used for datarecording can be reduced. Thus, efficient data recording can beperformed.

In the optical disc according to the present invention, pluralsynchronization patterns of data are arranged in devised manner withinthe linking area to thereby have ability to effectively performsynchronization establishment of data. Thus, data readability at thetime of reproduction is improved. In addition, end detection of blockreproduction is enhanced. As a result, the influence of step-out(pull-out) of synchronization by defect, etc. is difficult to be givento blocks of the succeeding stage. Thus, data readability at the time ofsequence reproduction is improved.

While explanation has been given in the above-described examples bytaking the example where the present invention is applied to the opticaldisc, since the form of the optical recording medium according to thepresent invention is arbitrary, the present invention can be applied tovarious forms such as tape shape and/or card shape, etc. without beinglimited to disc shape.

It is to be noted that while the invention has been described inaccordance with preferred embodiments thereof illustrated in theaccompanying drawings and described in the above description in detail,it should be understood by those ordinarily skilled in the art that theinvention is not limited to embodiments, but various modifications,alternative constructions or equivalents can be implemented withoutdeparting from the scope and spirit of the present invention as setforth and defined by appended claims.

INDUSTRIAL APPLICABILITY

As described above, in accordance with the optical recording mediumaccording to the present invention and the information processingapparatus using such recording medium, buffer areas are provided beforeand after block to thereby have ability to easily perform random access.Accordingly, the present invention is excellent in point of randomaccessibility as compared to the system of performing continuous writeoperation of block in the state where the linking portion does notexist. Further, linking area is formed by buffer areas overlapping witheach other so that any gap does not take place between blocks to therebyprevent drawbacks based on gap of reproduction waveform resulting fromexistence of the gap, e.g., change of the circuit design, switching ofoperational mode of circuit corresponding to presence/absence of gap,and/or switching of the circuit itself, etc. Thus, it is possible toguarantee compatibility of hardware. In addition, there is nopossibility that remarkable cost elevation may not be involved for thatpurpose.

1. An optical recording medium in which a write-once or rewriteoperation of data can be performed with a block including a group ofdata as a unit, wherein buffer areas having a fixed length for randomaccess are respectively disposed before and after respective blocks,whereby when a new block is recorded a start point for the fixed lengthbuffer area before the new block is not fixed relative to an existingblock preceding the new block, and the new block is recorded in a statethat the fixed length buffer area provided with respect to the new blockand the fixed length buffer area provided with respect to the existingblock adjacent to the new block overlap with each other, wherein thefixed length buffer area disposed immediately before a respective of theblocks includes a preamble for signal processing, and pluralsynchronization patterns having distances and identification informationthat are different from each other are recorded at the preamble.
 2. Theoptical recording medium as set forth in claim 1, wherein a recordingunit block is constituted by a respective of the blocks and the fixedlength buffer areas before and after the respective block, and a guardarea or areas is or are provided at a rear portion of one recording unitblock or at a rearmost portion of successive plural recording unitblocks.
 3. The optical recording medium as set forth in claim 1, whereinthe fixed length buffer area disposed immediately before a respective ofthe blocks includes a guard area for overlap at a time of recording, andsignal patterns for a frequency pull-in of a Phase Locked Loop (PLL) ata time of data reproduction and an Auto Gain Control (AGC) are recordedat the guard area or the preamble.
 4. The optical recording medium asset forth in claim 3, wherein the signal pattern is a repetitive patternof 3T/3T/2T/2T/5T/5T.
 5. The information processing apparatus as setforth in claim 3, further comprising: data reproducing means forreproducing a signal pattern recorded within a guard area for overlap ata time of recording of the fixed length buffer area or areas disposedimmediately before or immediately after a respective of the blocks, touse the signal pattern thus reproduced as a signal for automaticadjustment according to a power of a light source.
 6. The opticalrecording medium as set forth in claim 1, wherein the fixed lengthbuffer area or areas disposed immediately before or immediately after arespective of the blocks includes or include a guard area for overlap ata time of recording, and a signal pattern for automatic adjustmentaccording to a power of a light source is recorded within the guardarea.
 7. The optical recording medium as set forth in claim 6, whereinthe signal pattern is a repetitive pattern of 3T/3T/2T/2T/5T/5T.
 8. Theoptical recording medium as set forth in claim 1, wherein the fixedlength buffer area disposed immediately before a respective of theblocks includes a guard area for overlap at a time of recording.
 9. Theoptical recording medium as set forth in claim 1, wherein the fixedlength buffer area disposed immediately after a respective of the blocksincludes a postamble for time adjustment of signal processing and aguard area for adjustment of a recording end position, and a signalpattern for a Phase Locked Loop (PLL) according to a reproduction clockis recorded at the postamble.
 10. The optical recording medium as setforth in claim 9, wherein the signal pattern is a repetitive pattern of3T/3T/2T/2T/5T/5T.
 11. The optical recording medium as set forth inclaim 1, wherein the fixed length buffer area disposed immediately aftera respective of the blocks includes a postamble for time adjustment ofsignal processing and a guard area for adjustment of a recording endposition, and a signal pattern for detecting a reproduction end of theblock is recorded at the postamble.
 12. An information processingapparatus adapted for performing recording or reproduction ofinformation with respect to an optical recording medium in which awrite-once or rewrite operation of data can be performed with a blockincluding a group of data as a unit, the information processingapparatus including data recording means for generating recordingchannel data in which buffer areas having a fixed length for randomaccess are added before and after respective blocks to record the dataonto an optical recording medium, wherein when recording of a new blockis started with respect to a first block that has been already recorded,a start point for the fixed length buffer area before the new block isnot fixed relative to the first block preceding the new block, and thenew block is recorded in a state that the fixed length buffer areadisposed immediately before the new block and the fixed length bufferarea provided with respect to the new block overlap with each other, andwhen recording of the new block is completed, the new block is recordedin a state that the fixed length buffer area disposed immediately afterthe new block and the fixed length buffer area disposed immediatelybefore a next block adjacent to the new block overlap with each other,and further comprising data reproducing means for reproducing pluralsynchronization patterns recorded at a preamble for signal processing ofthe fixed length buffer area disposed immediately before a respective ofthe blocks to establish synchronization.
 13. The information processingapparatus as set forth in claim 12, wherein recording and reproductionare performed with recording a unit block including a respective of theblocks and the fixed length buffer areas before and after the respectiveblock as a processing unit, and a guard area or areas is or are providedat a rear portion of one recording unit block, or at a rearmost portionof successive plural recording unit blocks at a time of recording ofrecording channel data.
 14. The information processing apparatus as setforth in claim 12, wherein the fixed length buffer area disposedimmediately before a respective of the blocks includes a guard area foroverlap at a time of recording, the information processing apparatusfurther comprising: data reproducing means for reproducing a signalpattern recorded at the guard area or the preamble to use the signalpattern thus reproduced as a signal for a frequency pull-in of a PhaseLocked Loop (PLL) and an Auto Gain Control (AGC).
 15. The informationprocessing apparatus as set forth in claim 12, further comprising: datareproducing means for reproducing a signal pattern recorded at apostamble for time adjustment of a signal processing of the fixed lengthbuffer area disposed immediately after a respective of the blocks to usethe signal pattern thus reproduced as a Phase Locked Loop (PLL) of areproduction clock.
 16. The information processing apparatus as setforth in claim 12, further comprising: data reproducing means forreproducing a signal pattern recorded at a postamble for time adjustmentof a signal processing of the fixed length buffer area disposedimmediately after a respective of the blocks to perform detection of areproduction end according to the respective block.
 17. A recordingmethod for performing a write-once or rewrite operation of data with ablock including a group of data as a unit, wherein buffer areas having afixed length for random access are respectively disposed before andafter respective blocks, whereby when a new block is recorded, a startpoint for the fixed length buffer area before the new block is not fixedrelative to an existing block preceding the new block, and the new blockis recorded in a state that the fixed length buffer area provided withrespect to the new block and the fixed length buffer area provided withrespect to the existing block adjacent to the new block overlap witheach other, wherein the fixed length buffer area disposed immediatelybefore a respective of the blocks includes a preamble for signalprocessing, and plural synchronization patterns having distances andidentification information that are different from each other arerecorded at the preamble.
 18. The recording method as set forth in claim17, wherein a recording unit block is constituted by a respective of theblocks and the fixed length buffer areas before and after the respectiveblock, and a guard area or areas is or are provided at a rear portion ofone recording unit block or at a rearmost portion of successive pluralrecording unit blocks.
 19. The recording method as set forth in claim17, wherein the fixed length buffer area disposed immediately before arespective of the blocks includes a guard area for overlap at a time ofrecording, and signal patterns for a frequency pull-in of a Phase LockedLoop (PLL) at a time of data reproduction and an Auto Gain Control (AGC)are recorded at the guard area or the preamble.
 20. The recording methodas set forth in claim 19, wherein a repetitive pattern of3T/3T/2T/2T/5T/5T is recorded as the signal pattern.
 21. The recordingmethod as set forth in claim 17, wherein the fixed length buffer area orareas disposed immediately before or immediately after a respective ofthe blocks includes or include a guard area for overlap at a time ofrecording, and a signal pattern for automatic adjustment according to apower of a light source is recorded within the guard area.
 22. Therecording method as set forth in claim 21, wherein a repetitive patternof 3T/3T/2T/2T/5T/5T is recorded as the signal pattern.
 23. Therecording method as set forth in claim 17, wherein the fixed lengthbuffer area disposed immediately before a respective of the blocksincludes a guard area for overlap at a time of recording.
 24. Therecording method as set forth in claim 17, wherein the fixed lengthbuffer area disposed immediately after a respective of the blocksincludes a postamble for time adjustment of signal processing and aguard area for adjustment of a recording end position, and a signalpattern for a Phase Locked Loop (PLL) according to a reproduction clockis recorded at the postamble.
 25. The recording method as set forth inclaim 24, wherein a repetitive pattern of 3T/3T/2T/2T/5T/5T is recordedas the signal pattern.
 26. The recording method as set forth in claim17, wherein the fixed length buffer area disposed immediately after arespective of the blocks includes a post-amble for time adjustment ofsignal processing and a guard area for adjustment of a recording endposition, and a signal pattern for detecting a reproduction end of theblock is recorded at the post-amble.